Magnetic random access memory (MRAM) in which a magnetic tunnel junction (MTJ) element exhibiting the tunneling magneto resistive (TMR) effect is used for a data memory unit is drawing attention as a high-speed and large-capacity nonvolatile memory. Writing to the recording layer of the MTJ element is performed by, for example, a spin-transfer torque writing system that passes a current directly through the MTJ element and uses a spin-transfer torque injected from the reference layer of the MTJ element to reverse the magnetization of the recording layer. Here, to achieve a large capacity of memory, it is necessary to downsize the MTJ element to arrange data memory units in high density and to reduce the current necessary for writing.